Category Archives: Logic of Relatives

Peirce’s 1870 “Logic of Relatives” • Comment 12.3 We now have two ways of computing a logical involution raising a dyadic relative term to the power of a monadic absolute term, for example, for “lover of every woman”. The first method … Continue reading →

Peirce’s 1870 “Logic of Relatives” • Comment 12.2 Let us make a few preliminary observations about the operation of logical involution which Peirce introduces in the following words. I shall take involution in such a sense that will denote everything … Continue reading →

Peirce’s 1870 “Logic of Relatives” • Comment 12.1 To get a better sense of why Peirce’s formulas in Selection 12 mean what they do, and to prepare the ground for understanding more complex relational expressions, it will help to assemble the … Continue reading →

On to the next part of §3. Application of the Algebraic Signs to Logic. Peirce’s 1870 “Logic of Relatives” • Selection 12 The Sign of Involution I shall take involution in such a sense that will denote everything which is … Continue reading →

Peirce’s 1870 “Logic of Relatives” • Comment 11.24 We come to the last of Peirce’s observations about the “number of” function in CP 3.76. NOF 4.4 It is to be observed that Boole was the first to show this connection between … Continue reading →

Peirce’s 1870 “Logic of Relatives” • Comment 11.23 Peirce’s description of logical conjunction and conditional probability via the logic of relatives and the mathematics of relations is critical to understanding the relationship between logic and measurement, in effect, the qualitative … Continue reading →

Peirce’s 1870 “Logic of Relatives” • Comment 11.22 Let’s look at that last example from a different angle. NOF 4.3 So if men are just as apt to be black as things in general, where the difference between and must … Continue reading →

Peirce’s 1870 “Logic of Relatives” • Comment 11.21 One more example and one more general observation and we’ll be caught up with our homework on Peirce’s “number of” function. NOF 4.3 So if men are just as apt to be … Continue reading →

Peirce’s 1870 “Logic of Relatives” • Comment 11.20 We come to the last of Peirce’s statements about the “number of” function, first quoted in Selection 11 and again with the whole set in Comment 11.2. NOF 4.1 The conception of multiplication we … Continue reading →

Peirce’s 1870 “Logic of Relatives” • Comment 11.19 Up to this point in the 1870 Logic of Relatives, Peirce has introduced the “number of” function on logical terms, such that and discussed the extent to which its use as a … Continue reading →