‘The detail is open to interpretation,’ said the machine. ‘Take this unit, for example. I am no abominable intelligence as your attitude implies you believe me to be. My responses are not spontaneously generated, but predetermined. The servitors that make up my being are sanctioned for use. They are not machines, and what they generate – me, the Cawl Inferior – is not a unique creation but a limited expression of Archmagos Belisarius Cawl’s mind. By these means, I am free of the wickedness of forbidden sentience.

‘Archmagos Belisarius Cawl is a genius. Consider this unit further. The hexidecimal encoding that he projects to this unit is immune to decryption, for it is incomplete. My responses are inherent to this unit’s cogitators. An astropathic message can be intercepted, no matter how many locks are put upon it. Anything that uses the electromagnetic spectrum is worse. Not only can it degrade, or be captured, or be lost, but the journey of a message from where Cawl is now to where you are would take three thousand Terran years. Expediency is the enemy of dogma. You have asked him to be expeditious. He alone has been able to unlock, understand and improve upon the work of the Emperor. He alone is the master of a hundred fields of technology. He alone is unafraid of innovation. He is the best candidate to rule Mars. I present his petition to you. Give Archmagos Belisarius Cawl Mars, and he will hand you the galaxy.’

Guilliman had of course considered doing exactly this, but he did not lie to the Cawl Inferior. The result could be outright civil war in the Adeptus Mechanicus’ sub-empire of forge worlds.

‘Your colleagues would disagree with your evaluation,’ he said. ‘It cannot be done.’

‘I have no colleagues.’

‘His colleagues then.’

‘His colleagues are limited. Their beliefs have become a faith that they dare not challenge. The Adeptus Mechanicus is far more trammelled in its thinking than the Mechanicum of your time was, my Lord Guilliman, and the archmagos was a radical in those distant centuries. You would not have come to him if he were not. Already you have asked him to perform many forbidden duties. You are as culpable as he in any crime that may or may not have taken place.’

‘I am no adherent of the Machine-God’s creed,’ said Guilliman.

‘You have asked the archmagos to interfere with technologies expressly forbidden by your own creator, the Emperor of Mankind.’

The machine waited expectantly, far too lifelike for a supposedly lifeless machine.