信而有征 is an idiom

信而有征xìn ér yǒu zhēng

borne out by evidence

信：确实；征：征验，证据。可靠而且有证据。

Origin 《左传·昭公八年》：“君子之言，信而有征。”

Example 称多则吾岂敢，言拙～。（晋·潘岳《闲居赋》）

Word breakdown for “信而有征”: Open in Reader →

信HSK 2

1.letter2.mail3.to trust4.to believe+6 more +7 more

而HSK 4

1.and2.as well as3.and so4.but (not)+4 more +5 more

有HSK 1

1.to have; there is2.(bound form) having; with; -ful; -ed; -al (as in 有意[yǒu yì] intentional)

征HSK 7–9

1.journey2.trip3.expedition4.to go on long campaign+1 more +2 more

征徵HSK 7–9

1.to invite2.to recruit3.to levy (taxes)4.to draft (troops)+4 more +5 more