Both Uses

principle
in
A Doll's House
(Auto-generated)

All your father's want of principle—be silent!†
Act 3 *

principle = basic rule or belief
—all your father's want of principle has come out in you.†
Act 3

Definitions:

(1) (principle)
a basic rule or belief
The exact meaning of principle can depend upon its context. For example:
- "our guiding principles" -- basic moral beliefs that guide decisions and behavior
- "electromagnetic principles" -- rules describing how the world works
- "She lacks principles." -- lacks moral guidelines
- "We agree in principle." -- about important basic beliefs
(2) (meaning too rare to warrant focus)
See a comprehensive dictionary for more specialized senses including one in chemistry.