Theorem 4pos

Description: The number 4 is positive. (Contributed by NM, 27-May-1999)

	Ref	Expression
Assertion	4pos	$$⊢0<4$$

Proof

Step	Hyp	Ref	Expression
1		3re	$$⊢3\in ℝ$$
2		1re	$$⊢1\in ℝ$$
3		3pos	$$⊢0<3$$
4		0lt1	$$⊢0<1$$
5	1 2 3 4	addgt0ii	$$⊢0<3+1$$
6		df-4	$$⊢4=3+1$$
7	5 6	breqtrri	$$⊢0<4$$