How We Naturally Reason

In the 17th century, Hobbes stated that we reason by addition and subtraction. Historians of logic note that Hobbes thought of reasoning as “a ‘species of computation’” but point out that “his writing contains in fact no attempt to work out such a project.” Though Leibniz mentions the plus/minus character of the positive and negative copulas, neither he nor Hobbes say anything about a plus/minus character of other common logical words that drive our deductive judgments, words like ‘some’, ‘all’, ‘if’, and ‘and’, each of which actually turns out to have an oppositive, character that allows us, “in our silent reasoning,” to ignore its literal meaning and to reckon with it as one reckons with a plus or a minus operator in elementary algebra or arithmetic. These ‘logical constants’ of natural language figure crucially in our everyday reasoning. Because Hobbes and Leibniz did not identify them as the plus and minus words we reason with, their insight into what goes on in ‘ratiocination’ did not provide a guide for a research program that could develop a +/- logic that actually describes how we reason deductively. I will argue that such a +/- logic provides a way back from modern predicate logic—the logic of quantifiers and bound variables that is now ‘standard logic’—to an Aristotelian term logic of natural language that had been the millennial standard logic.
Keywords logic  term logic  predicate logic  ratiotination  Aristotle  Frege  Deductive Reasoning  Cognitive Science
Categories (categorize this paper)
 Save to my reading list
Follow the author(s)
Edit this record
My bibliography
Export citation
Find it on Scholar
Mark as duplicate
Request removal from index
Revision history
Download options
Our Archive
External links

Setup an account with your affiliations in order to access resources via your University's proxy server
Configure custom proxy (use this if your affiliation does not provide a proxy)
Through your library
References found in this work BETA

No references found.

Add more references

Citations of this work BETA

No citations found.

Add more citations

Similar books and articles
Ratiocination: An Empirical Account.Fred Sommers - 2008 - Ratio 21 (2):115–133.
Reasoning, Logic and Computation.Stewart Shapiro - 1995 - Philosophia Mathematica 3 (1):31-51.
Logic or Reason?Penelope Rush - 2012 - Logic and Logical Philosophy 21 (2):127-163.
Deductive Logic.D. S. Clarke - 1973 - Carbondale: Southern Illinois University Press.
Logic, Reasoning and the Logical Constants.Pascal Engel - 2006 - Croatian Journal of Philosophy 6 (2):219-235.
Informal Logic.Leo Groarke - 1996 - Stanford Encyclopedia of Philosophy.
Logic and Analyticity.Tyler Burge - 2003 - Grazer Philosophische Studien 66 (1):199-249.
Field on the Normative Role of Logic.Gilbert Harman - 2009 - Proceedings of the Aristotelian Society 109 (1pt3):333 - 335.
Reasoning and Logic.Jim Mackenzie - 1989 - Synthese 79 (1):99 - 117.
Added to PP index

Total downloads
207 ( #20,402 of 2,197,333 )

Recent downloads (6 months)
14 ( #14,098 of 2,197,333 )

How can I increase my downloads?

Monthly downloads
My notes
Sign in to use this feature