The Seattle Times has an editorial that I and many other housing advocates could have written ourselves; the editorial affirms what we’ve been saying over and over again, increasing supply in the face of rising demand will have a positive effect on prices for renters. I have called the stubborn and ideological resistance to this the Galileo Problem. So many smart people resist the notion of increasing housing supply simply because they worry someone might make more profit. That shouldn’t matter (even though profit is related to risk, not increasing supply) since we know more housing will help poorer people compete against people with more money to spend on housing. But you’ve heard me say that. Here’s the Times saying it:

SEATTLE Mayor Ed Murray’s new task force comes at the right time to help the city avoid a full-blown housing crisis as its population swells over the next two decades.

But that would only happen if the 28-member committee, tasked with creating a long-term plan to address housing affordability, produces effective solutions — not just analysis — and does more than duplicate efforts already under way.

At a news conference last week, city leaders cited anecdotes about prospective renters having a hard time finding apartments or families seeing rents go up to prices they cannot afford. But, no one provided any hard data to quantify how many households can no longer afford Seattle or what the true need is.

Last July, the mayor received a 19-page report and list of suggestions from a special committee that spent a year analyzing how to improve existing affordable-housing incentives. The consensus: They work, improve them and use them more.

The Seattle Planning Commission is already working on a major update due next year to the city’s Comprehensive Plan, which outlines where to build new housing and increase density. The plan was established in 1994 and has helped shape the city since.

Job growth and Seattle’s desirability as a place to live keep pushing up demand, which leads to higher housing costs. Close to 44,000 people moved to Seattle in the past four years and another 120,000 are projected to arrive during the next 20.

Housing development also ballooned in recent years: Builders added 35,600 homes, including houses and apartments, from 2005 to 2013. Without those homes, housing costs would be even higher.

The city’s rapid growth demonstrates its capacity to accommodate new residents. Increasingly, they are single people living alone, and poor people and families are on their way out.

City officials say they want affordable housing for all and that housing should be fair and equitable — important ideals. But what’s clear is that Seattle needs more housing that is subsidized and market-rate.

The mayor’s committee should focus on how to get more building cranes in the air.