Theorem nftru 1488

Description: The true constant has no free variables. (This can also be proven in one step with nfv 1550, but this proof does not use ax-17 1548.) (Contributed by Mario Carneiro, 6-Oct-2016.)

Assertion

Ref	Expression
nftru	⊢ Ⅎ𝑥⊤

Proof of Theorem nftru

Step	Hyp	Ref	Expression
1		tru 1376	. 2 ⊢ ⊤
2	1	nfth 1486	1 ⊢ Ⅎ𝑥⊤

Syntax hints:  ⊤wtru 1373  Ⅎwnf 1482

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-gen 1471

This theorem depends on definitions:  df-bi 117  df-tru 1375  df-nf 1483

This theorem is referenced by:  nfmo  2073  dvelimc  2369  nfralw  2542  nfralxy  2543  nfrexw  2544  nfralya  2545  nfrexya  2546  nfreuxy  2680  nfsbc  3018  nfsbcw  3127  nfcsbw  3129  nfcsb  3130  nfiotaw  5233  nfriota  5899  nfixpxy  6794