Malcolm Turnbull and Bill Shorten. Credit:Alex Ellinghausen There are two. First, the strategy of trying to fix the budget deficit solely on the spending side has been a dismal failure. Only a more balanced approached is likely to be politically acceptable. The Coalition will do itself a disservice if it believes its own bulldust that it did so poorly purely because of the success of Labor's big lie about privatising Medicare. More on that another day. The strategy of the Abbott government's first budget was to return the budget to surplus by cutting government spending while avoiding tax increases or cuts in tax concessions almost completely. The public's reaction was so hostile Tony Abbott was rendered unre-electable. But, though few of those measures went through, Scott Morrison has persisted with the strategy by repeatedly claiming the budget has a spending problem, not a revenue problem.

Such a strategy involves fixing the budget at the expense of low and middle income-earners, while largely shielding high income-earners and business. The political arithmetic of this was always what Sir Humphrey would call "courageous" and so it proved on Saturday. Remember, the Turnbull government's plans still included huge cuts in grants to the states for public hospitals and schools, plus measures doctors claimed would force them to stop bulk-billing. Plus an unspecified future increase in university fees. Many voters would also remember the enormous stuff-up of the attempt to privatise technical and further education. On the other side of the budget, the Coalition has acted as though fixing the deficit by increasing taxes or cutting concessions was economic and political anathema.

This is nonsense - as the election shows. The government actually went to the election with plans to increase taxes, on tobacco and on multinational companies, which drew no criticism. Its plan to cut superannuation tax concessions drew noisy criticism from a few people who would never have not voted Liberal. Its heavy past – and future – reliance on bracket creep drew no criticism. Nor did Labor's plan to continue the temporary "budget repair" levy on high income-earners. Point is, the Coalition's willingness to propose tax increases came only to help pay for its planned phase-down in the rate of company tax, not as part of its efforts to return the budget to surplus. It lost votes for wanting to cut company tax, thus reducing any political benefit from its plan for jobs and growth. In any case, the cuts are now unlikely to get far in the Senate.

Message: we won't achieve much in fixing the budget until we're prepared to increase tax as well as cut spending and, in the process, share the burden more fairly between the top, middle and bottom. The election result's second lesson is that, in our efforts to make "reforms" that increase economic efficiency and improve our productivity, we should stop gratifying rent-seeking by big business and start listening to other advice, including the majority of recently polled economists saying the long-run growth dividend from spending on education is greater than an equivalent amount spent on business tax cuts. We should abandon the voter-rejected experiment with reform via tax changes and shift to productivity-enhancing reform of education, infrastructure and, would you believe, health (because health is one of our biggest and fastest growing industries, but quite inefficient). If you think this conflicts with all I've just said about repairing the budget in ways voters will accept, it's clear we – and, more particularly, our pollies and their econocrat advisers – have a lot more thinking to do. Lifting our productivity via education, infrastructure and health doesn't have to involve spending a lot more on them, and may well involve achieving slower rates of spending growth.