Useful evidence depends on the question

1 · Learn

Original source A, a council notice: The footbridge will close for four weeks while damaged decking is replaced. The signed diversion adds approximately ten minutes to the usual walk. Emergency access remains available by the road bridge. Original source B, a resident's letter: Ten minutes on paper is not ten minutes with a tired child and shopping. I welcome the repair, but the notice treats a daily routine as a line on a map. Please provide clearer resting points along the diversion.

The notice is useful for the planned closure duration; the letter is useful for one resident's concern about the diversion. Neither alone establishes how every resident will be affected. A source can be useful for one purpose and limited for another.

Ask who produced it, for whom, when and to answer which question. A viewpoint does not make a source worthless, but it influences what its evidence can establish.

2 · Worked example

To find the planned duration, A gives four weeks. To understand one access concern, B supplies an example, not a representative survey.

3 · Your turn

Can the letter alone establish that every resident needs resting points? Explain.

4 · Apply your learning

Choose the better source for two different questions and justify both selections with limits.