GRAMMAR DETAIL

ことから

judging from the fact that

Presents an observed fact as the basis for a judgment or inference.

Examples

窓が割れていることから、外から石が当たったと分かった。

From the fact that the window was broken, I realized that a stone had struck it from outside.

煙が見えないことから、火は消えたと判断した。

Since no smoke was visible, I concluded that the fire was out.

足跡が新しいことから、近くに動物がいると考えた。

Judging from the fresh tracks, I thought there was an animal nearby.

Structure: こと packages the preceding content as a fact, and から marks it as the starting point for a judgment, linking observation to inference.
Basic usage: 煙が見えないことから、火は消えたと判断した。 uses the absence of visible smoke as grounds for concluding that the fire was out.

Evidence and conclusion
- 煙が見えない is the observation, while 火は消えたと判断した reports the judgment drawn from it. ことから does not itself guarantee the certainty of every inference.
Connecting a fact
- An i-adjective connects directly, as in 新しいことから, but a na-adjective uses な, as in 静かなことから. A noun can be presented as a fact with a form such as 会員であることから.