Noesis is difficult to describe because it falls into no traditional category. It is more than a search engine, more than an online library of philosophical content, more than an index of links, more than a bibliography, more than a discussion forum.

Primarily, Noesis organizes the philosophical content on the web. Its ultimate purpose is to make it easier for authors to find readers and readers to find content on any philosophical topic. It does this in four basic ways:

1. Searching
2. Browsing
3. Collecting (carving out a subset or user library of items to suit your needs, and making your libraries available for use by others)
4. Endorsing (declaring an item to be worth reading, and making your endorsements available for use by others)

Endorsing items puts them into special user libraries, and creating user libraries endorses the items they contain. In this sense collecting and endorsing are the same activity. However, to appreciate the power of Noesis, it helps to separate them. Sometimes you will want to collect without regard to the endorsing effect, and sometimes to endorse without regard to the collecting effect. Moreover, though it is true that when you collect, you endorse, and vice versa, you do neither when you use the collections of others or rely on their endorsements.

In addition to these four basic services, Noesis offers many other services not described on this overview. For example, it allows users to add content to the dataset, it provides permanent URLs for philosophical web sites, it provides electronic snapshots of trends in the profession, it hosts philosophical discussions, and much more.

Let's look at the four basic services in more detail.

Searching

• Noesis permits very flexible searching.
  • Noesis supports wildcards. Use the asterisk to match all endings. For example, Plat* will retrieve "Plato" and "Platonic" and "Platitude".
  • Noesis supports boolean operators. It supports and, or, and not. It also supports parentheses to keep your boolean logic unambiguous, e.g. Plato and (forms or ideas).
  • Noesis supports phrase searching. Simply put the phrase in double quotation marks ("...").
• Noesis supports many kinds of search filters. Some are based on genre (primary texts, essays, reviews, course hand-outs, etc.). Some are based on origin (certain online journals, certain collections of Noesis content created by users). Some [coming in 3.0] are based on quality (endorsements by Noesis professional users). Adding filters has the effect of "zooming in" for fewer hits and more discrimination. Removing filters has the effect of "zooming out" for more hits and less discrimination.
• You can search the whole collection or any subset you care to define.
• You can put a search box on another web page. It can cover the whole collection or any defined subset (such as your own works or an anthology you've created for a course). All filters are available to such remote search boxes.
• You can link to a search in Noesis from another site. Every time you click on the link, you jump to Noesis and perform the search. It may be set to cover the whole collection or any defined subset.
• [Coming in 3.0] Noesis supports current awareness. Once you refine a search to pick out just the topic you need, you can store it and have Noesis run it automatically at user-determined intervals. Noesis will notify you of new hits by email after each run.

Collecting and Endorsing

• Noesis allows professional users to carve out subsets of the Noesis content. These subsets are called user libraries. Each user library has a name [coming in 3.0] and unique URL. You might want a user library to function as a course-pack, a virtual reserve shelf, an anthology, a bibliography, or a library of sources relevant to your research.
• You can set up the Noesis search box to search just the contents of any given user library. You can also put such a search box on any remote site. For example, if you create a user library to function as a course-pack for your students, you could put a search box for that library on your own home page.
• User libraries can have hierarchical structure. If you like, you may organize the items in a library under rubrics (Week 1, Week 2, Week 3, etc., or Locke, Berkeley, Hume, etc.) and display the contents of your library as an outline.
• You can search and browse any user libraries, not just those you created yourself. You can find a given user library under the name of the creating user (in the Professional Registry). Or [coming in 3.0] you can search for them by name or topic.
• Selecting an item for inclusion in a user library is an endorsement of that item. For this purpose, endorsing an item is only to say that it is worth reading.
• Because endorsement is limited to professional users, the creation of user libraries is also limited to professional users.
• Noesis uses endorsements many ways to help users. First, it uses them to create user libraries. Second, [coming in 3.0] it can calculate the "most endorsed endorsers" and let users filter their searches accordingly. The result allows natural authority to emerge from the democratic process of endorsements. Third, [coming in 3.0] it builds "user libraries" withouts "users". The software alone, with the entire history of user endorsements, creates libraries of the most endorsed content in a given topic or branch of the field. Finally, [coming in 3.0] it uses trends in endorsements to show trends in the profession.
• [Coming in 3.0] A group of professional users with a common expertise in a certain topic can create a peer-reviewed journal on that topic using the Noesis endorsement functions. They register their intent to create an online journal, indicate how many members are on their editorial board, and how many endorsements are needed to include an item in the journal. For example, a board of 10 members might decide that any item endorsed by eight or more of the editors will be accepted into the journal. The journal is simply a user library created by this group method of endorsement. But because it functions exactly like a journal (except in permitting retroactive peer review of content already published on the web), it is listed with the other journals.

Browsing

• If you'd rather browse than search, Noesis gives you many browsing options. You may browse the contents of any journal indexed by Noesis. Or you may browse any user library —those you have created yourself and those created by others. Note that these are two different ways to browse content filtered by peer-review. To browse the contents of peer-reviewed journals is to harness traditional, prospective peer review. To browser a user library is to harness the alternative, retroactive peer review made possible by Noesis endorsements.
• Noesis 2.0 was launched with some exemplary user libraries created by hand-picked experts. These are examples of what any professional user can construct.
• [Coming in 3.0] You will soon be able to browse "user libraries" built by the Noesis software. The advantage is that they will be more comprehensive and up to date on the topic than any library built by a human user could be. Moreover, these software-built libraries can be limited to items endorsed by a certain quotient of users, or a certain quotient of endorsed endorsers. This will enable you to browse the "cream of the crop" on a given topic, when the underlying judgments of quality are a software summary of the collective endorsements of Noesis users.

Noesis creates a zone of peer-reviewed quality on the web. But it does so in many ways. Here's a brief summary.

How Noesis uses peer-review

• Traditional peer review
  • Noesis indexes all peer-reviewed philosophy journals which have content on the web. This is traditional peer review. We don't make this obsolete and don't want to do so. On the contrary, we support it by helping online peer-reviewed journals find readers and helping readers find peer-reviewed journal articles.
  • Noesis allows users to limit a search to a given peer-reviewed journal or to our collection of peer-reviewed journals. This in effects puts a "quality filter" on a search to limit hits.
• Noesis introduces a new form of retroactive peer-review called endorsement.
  • Professional users may endorse any item in the Noesis dataset with a single click.
  • Only registered professional users may endorse items. Professional users are limited to those who have a Ph.D. (or equivalent doctoral degree) in philosophy, or who are ABD in philosophy. The rationale for this limitation is to preserve the "peer" quality of peer review. Only users with advanced credentials in philosophy should be allowed to tell other users what is worth reading in this field. Non-professional users may use every other feature of Noesis.
  • Endorsements are revocable. At any time, the maker of an endorsement may delete it, with one click.
  • Users can tell which items have been endorsed and which have not. With a single click, a user can see the list of endorsers for every endorsed item, and the list of endorsed items for every endorser.
  • Endorsing an item puts it into a special subset called a user library. [Coming in 3.0] Professional users can create any number of user libraries, e.g. one for their own works, one for each course they teach, one for their research, and so on. All user libraries have names [coming in 3.0] and unique URLs.
  • Because only professional users can endorse items, only professional users can create user libraries. However, all user libraries are available to all users for browsing and searching. Because all user libraries consist of endorsed items, browsing or searching a user library is another way of using peer review to filter the dataset.