Open main menu
Home
Random
Recent changes
Special pages
Community portal
Preferences
About Wikipedia
Disclaimers
Incubator escapee wiki
Search
User menu
Talk
Dark mode
Contributions
Create account
Log in
Editing
First principle
(section)
Warning:
You are not logged in. Your IP address will be publicly visible if you make any edits. If you
log in
or
create an account
, your edits will be attributed to your username, along with other benefits.
Anti-spam check. Do
not
fill this in!
== In formal logic == In a formal [[logical system]], that is, a set of [[proposition]]s that are consistent with one another, it is [[Logical possibility|possible]] that some of the statements can be deduced from other statements. For example, in the [[syllogism]], ''"All men are mortal; Socrates is a man; Socrates is mortal"'' the last claim can be deduced from the first two. A first principle is an [[Axiom#Mathematical logic#Logical axioms|axiom]] that cannot be deduced from any other within that system. The classic example is that of [[Euclid's Elements|Euclid's ''Elements'']]; its hundreds of geometric propositions can be deduced from a set of definitions, postulates, and [[primitive notion]]s: all three types constitute first principles.
Edit summary
(Briefly describe your changes)
By publishing changes, you agree to the
Terms of Use
, and you irrevocably agree to release your contribution under the
CC BY-SA 4.0 License
and the
GFDL
. You agree that a hyperlink or URL is sufficient attribution under the Creative Commons license.
Cancel
Editing help
(opens in new window)